Automatic variable speed rewind drive



Aug. 3, 1965 Filed May 15, 1963 c. AARON 3,198,453

AUTOMATIC VARIABLE SPEED REWIND DRIVE 5 Sheets-Sheet 1 Aug. 3, 1965 c. AARON AUTOMATIC VARIABLE SPEED REWIND DRIVE 5 Sheets-Sheet 2 Filed May 15, 1963 INVENTOR.

Aug. 3, 1965 c. AARON AUTOMATIC VARIABLE SPEED REWIND DRIVE 3 Sheets-Sheet 3 Filed May 15, 1963 United States Patent York Filed May 15, 1963, der. No. 230,526 7 Claims. (Ci. 242-65) This invention relates to improvements in rewind machines and more particularly to improvements in control means therefor.

Rewind machines embodying the invention are particularly adapted for receiving a relatively wide mill or supply roll, unwinding same and passing the sheet material or webbing past a series of slitters or cutters whereby the material is cut into a series of longitudinal strips or subwebs. The webbing then passes partially around a contact drum from whence it is wound upon rewind shafts forming rewind rolls.

The invention is adapted for providing a rewind machine such as may be utilized by a manufacturer who has need to rewind a variety of different materials such as light, heavy, stretchy or relatively stifi plastics, and laminates of all types, waxed or coated papers, kraft, foil, and impregnated fabrics and other materials, for example. It is to be pointed out that all of the aforementioned materials may vary in gauge thickness across the width of the web thereof.

Further, in accordance with the invention, the construction is such that accurate quality control may be maintained of the finished rewind roll. For instance, in order to provide a commercially acceptable rewind roll, the edges thereof must be uniform and straight. The internal tension and density of the web material must be consistent throughout the roll and the material cannot be distorted or scorched in the process.

' Rewind rolls which are made from web material which varies in thickness across the web, will when wound on a common mandrel, tend to build up to unequal diameters. If such rolls are locked to the rewind mandrel some of the rolls will tend to have peripheral velocities which are greater than that of the oncoming web strip and others will tend to have velocities which are too low. Hence, the resulting rolls tend to be either too highly tension ed or too loosely wound.

The aforementioned difiiculty is overcome by employing individual driving collars which are urged axially by pneumatic or spring means on the rewind mandrels and thus driving individual cores while permitting them to partially slip in relation to the mandrel, thereby assuring a peripheral speed consistent with that of the oncoming web strip. Tension in the strip is established by the amount of torque transmitted to the roll by the driving collars.

If the mandrel speed (rpm) is maintained constant for a given web speed, the slipping r.p.m. between the collars and cores becomes exceedingly large as the rewind diameter builds up and the core slows down. Heat generated in such a manner can become excessive and char the core including a considerable amount of adjacent web material. Also, under conditions of heavier torque transfer, control of the torque becomes discontinuous and inconsistent.

One method of alleviating the aforementioned condition has been to drive the rewind mandrel through a friction clutch which can dissipate heat energy effectively. In this device, the operator is required to adjust the clutch torque so that it is just suflicient to overcome the torque requirements at the drive collars at a small percentage of slip between core and collar. However, if the torque setting of the clutch is too high, the clutch will stop Patented Aug. 3 1955 slipping and the mandrel speed will tend to reach a constant high value and produce excessive core heat. If the clutch torque is set too low, the mandrels will stop slipping in the cores and the differential rewinding action will be lost.

Another method that has been employed heretofore is to drive the mandrels with variable speed drives which may be mechanical, hydraulic or electrical in nature. Such drives will change speed in response to a diameter build up and a change in' speed of the web passing through the machine. However, the inherent disadvantages of such variable speed drives are high costs and complexities.

This invention comprises means for inexpensively providing a controlled variable speed drive to the rewind drive mandrels by automatically adjusting the torque of a pneumatically actuated friction clutch to the proper value in relation to the torque requirements of' the driving collars. If the speed of the mandrel, at a given machine speed and rewind diameter, is too high the clutch torque is automatically reduced until the speed drops to a desired, pre-programmed value. If the mandrel speed is, too low, the clutch torque is increased until the speed is raised to the desired value. In this manner the mandrel speed can be controlled at a fixed percentage above; the actual speed of the core throughout the roll build-upand a wide range of web speeds.

The rewind machine is shown by way of'illustration as embodied in a machine of the'duplex type; that is, where the machine comprises a front portion and a rear portion each of which contain a group of rewind rolls. However, certain features of the invention are useful in machines of other types.

In view of the foregoing, one of the principal objects of my invention is to provide control means which regulate the torque input into the rewind mandrel or .mandrels in response to a composite of three primary actuating signals. The first signal is responsive to the build-up of the web material upon the rewind roll. As the web material builds up upon the rewind roll, the rewind roll increases in diameter and, therefore, requires the rewind arm to pivot outwardly away from the contact drum providing space for the additional material and thereby increasing the angle of inclination of the rewind arms. The build-up of the web material upon the rewind roll is significant because the rewind shaft speed must decrease as the rewind roll diameter increases so that a constant surface speed of the rewind roll is maintained which corresponds to the web feed speed. Secondly, the control means are actuated by an input signal responsive to the speed of the machine. This speed .is important ,because a different speed is required for different types of Web material in order to provide a satisfactory rewind pattern, and the torque input into the rewind roll should correspond thereto. The third input signal into the control means is I responsive to the actual speed of the rewind shaft.

In order to achieve the aforementioned features and objects my invention contemplates a rewind machine comprising the combination of at least one pair of rewind arms pivotally supported at their inner ends andadapted to support a rewind shaft at their outer ends on which shaft a web or webs of sheet material are to be wound into rewind rolls. A contact drum is adapted for operational engagement with the rewind roll, The angular position of the rewind anns varies in accordance with the variation in the diameters of the rewind rolls. One of the rewind arms carries at its outer end means for driving engagement with the shaft. Motive .means are provided which have .a substantially constant or slightly increasing torque output. Said motive means are drivingly connected to the rewind shaft means for'driving engagement. The motive means may comprise clutchmeans, if desired."

The motive means are provided with control means which operate in response to the speed of the rewind shaft, the speed of the motive means and the angular position of the rewind arms.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, addi tional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention.

Specific embodiments of the invention have been chosen for purposes of illustration and description, and are shown in the accompanying drawings, forming a part of the specification, wherein:

In the drawings:

FIG. 1 is a side elevation showing one embodiment of a rewind machine constructed in accordance with this invention;

FIG. 2 is a sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is a schematic diagram showing the ratio control station;

FIG. 4 is a graphical showing of the relationship between the rewind roll diameter and the mandrel speed depicted by air pressure for various web feed speeds; and

FIG. 5 is a schematic view illustrating the control elements.

Referring now to the drawings and particularly to FIG. 1 thereof, there is illustrated a duplex rewind machine which comprises a front portion designated generally at and a rear portion designated generally at 12. A supply roll 14, comprising mill supply or sheet material which is to be rewound, is mounted on a supply roll shaft which is positioned within suitable proximity to the remainder of the rewind machine. A web 16 is fed from the supply roll 14, over an idler roll 18, around a cutting roll and partially around a contact drum 22. The rolls 18 and 20 and drum 22 have torque applied to their center shafts 19, 21 and 23, respectively, if desired, in order to draw the web towards the rewind stations and to minimize the friction of the web when passing thereover. Slitters or cutters 24 are provided adjacent the cutting roll 20 to cut the web into strips or subwebs of the desired rewind widths as the web material passes thereby. From the contact drum 22, the web 16 is led to the series of rewind rolls 26 and 28. Alternate strips of webbing pass first to the front rewind roll 26 and the next adjacent strip passes to the rear rewind roll 28 or vice versa. The rewind rolls 26 and 28 are supported by the rewind roll shafts or mandrels 30 and 32, which are carried by pairs of rewind arms 34 and 36, respectively. As the web 16 builds up on the rewind roll 26, the diameter thereof increases and the rewind arms move outwardly in an arcuate manner. Likewise, the rear rewind arms 36 function in a similar manner.

Referring now to FIG. 2 motive means is provided by an electric motor 38 which rotates drive shaft 40 through a coupling member 42. Fixedly connected to the drive shaft 40 are a plurality of drive gears 44, 46 and 48. Two of the driving gears, namely 46 and 48, are used to drive the center shafts 21 and 23 through suitable gear trains (not shown). A gear train designated generally at 50 is driven by means of the drive gear 44 and is composed of a series of inter-meshing gears each of which is supported by a shaft which is rotatably mounted in one of the rewind arms 34 or 36. The gear train 50 drives a shaft 52 which in turn is positively connected to the driving side 54 of a I for the convenience of the operators.

clutch S5. The driven side 56 of the clutch 55 drives a gear 58 by means of shaft 60. The driving member of the clutch 55 is actuated in a manner which will be described more fully hereinafter.

Still referring to FIG. 2, gear 58 drives gear 72 which is keyed to and drives rewind shaft or mandrel 30. Mounted on rewind shaft 38 are a plurality of rewind roll cores, two being shown at 74 and 76. Adjacent the cores and mounted on the rewind shaft 30 are driving collars 73, 8t and 84 which rotate with the shaft because of pins which fit in longitudinal grooves in the shaft. Spacer 86 is provided in order to axially position the rewind rolls 90 and 92 of the series of rewind rolls 26. Means are provided for applying an axial compressive force; actually this force has been produced successfully in several different ways, such as by means of spring loaded shafts or by a pneumatic system. One of the latter systems is illus-' trated in FIG. 2, wherein a pneumatic cylinder 94 contains a piston 96 whose movement is responsive to air pressure 98 supplied from an outside source (not shown) through a manually operated pressure regulator 101. A coupling member 100 is connected to the piston 96 by means of piston rod 102, and the other side thereof presses against drive collar 84. The axial force, transmitted from the coupling member 100, urges the driving collars 78, 80 and 84 against the adjacent faces of their respective cores 74 and 76 with sufficient magnitude so that the driving torque exerted by rewind shaft or mandrel 39 is transmitted to the cores. Thus, the cores and their respective driving collars react in a manner similar to a slip clutch. It is to be noted that the axial force is not enough to lock the cores against their respective driving collars, but is just sufficient to allow some slippage so that each individual roll may set its own speed of rotation. The required force is determined by several factors including the characteristics of the material, speed of rewinding, width of the strips and others. In general, narrow strips require less force than do wide strips. Since the speed of the rewind shaft 30 is accurately controlled by means of the clutch 55, the amount of slippage between the driving collars and their respective cores is held to a practical minimum so that the heat generated thereby is negligible. Also, the air pressure utilized throughout the cycle is generally maintained relatively constant so that only an occasional adjustment is necessary.

FIG. 5 shows schematically the control means which actuate the clutch 55. Air is supplied from some convenient outside source 112 through a filter 114 and thence to the header 116. Air pressures willbe given nominal values herein for purposes of illustration, however, any other suitable pressures may be employed, as desired. A portion of the air from the header 116 is led through a regulating valve 118 which discharges air at a pressure of 5 p.s.i.g. into pipe line 120. A gauge 121 is provided Pipe line leads to a ratio control station 122. Another portion of the air in the header 116 is led to a regulating valve 124, from whence regulated air pressure at 20 p.s.i.g. is discharged into pipe line 126. Gauge 128 is also provided for the convenience of the operators. Pipe line 126 leads to a speed transmitter 104, to a second speed transmitter 106 and to the ratio control station 122. Still another portion of air from the supply header 116 is led to a regulating valve 138 which throttles the air to a pressure of 30 p.s.i.g. and discharges same into a pipe line 132, gauge 133 being provided. Pipe line 132 leads to a controller 134. Another portion of air from the header 116 leads to another regulating valve 136 which throttles the air pressure to 5 p.s.i.g. from whence it is discharged intoline 138 which leads to a selecting relay 142. Pressure gauge 140 is supplied as a matter of convenience. Still another line from the header 116 leads to line 144 which in turn leads to a manually adjustable regulating valve 146 and to an amplifying relay 148.

Speed transmitter 104 is interconnected with the electric,

motor 38 which is also shown in FIG. 1 and FIG. 2. The transmitter discharges air under pressure which is directly proportional to the rotational speed of the electric motor. Any suitable speed transmitting apparatus may be employed for this purpose. The output air pressure from the speed transmitter 104 ranges from three to fifteen p.s.i.g. and is transmitted through line 1519 to the selecting relay 142. The selecting relay 142 receives two signals and selects the higher of the two signals, which it transmits to line 154. Since line transmits a pressure of from three to fifteen p.s.i.g. and line 138 transmits a constant pressure of five p.s.i.g., the selecting relay will transmit a pressure the same as that received from line 150, but will have a minimum value of five p.s.i.g. Pipe line 154 then leads to the ratio control station 122. Any suitable selecting relay apparatus may be employed.

Speed transmitter 106 is similar to speed transmitter 1194 already described. It receives supply air from line 126 and is actuated by the rotational speed of gear 58. Air pressure is discharged therefrom, which is directly proportional to said speed and then introduced into line 156 which leads to the controller 134. Thus, in effect, an air signal is transmitted which is directly proportional to the rotational speed of the rewind shaft 30. Thisair pressure ranges from three to fourteen p.s.i.g.

Referring now to FIG. 3, a detailed diagrammatic view of the ratio control station 122 is shown. Any standard commercial controller that performs the functions hereinafter described is suitable for use with my invention. For example, Model No. 5403 as manufactured by Moore Products Company, Philadelphia, Pennsylvania is satisfactory. Line 120 having a constant reference pressure of five p.s.i.g. is led into one side of the ratio control station. A pressure gauge 158 is provided for the convenience of the operator. Air from transmitter 104 whose pressure is proportional to the machine or web speed first passes from line 154 through a fixed orifice at 166 and then through an adjustable orifice or needle valve at valve 150 before bleeding ofi at valve 118 in line 126 which maintains a constant back pressure of five p.s.i.g. The pressure in chamber 162 is a function of the relative resistances in orifices 160 and 166 and at any given time is dependent on the pressure in 154 and the opening or orifice in valve 166. Since the stem of the needle valve 160 is mechanically connected to the knob 110 (shown in FIG. 5) the size of its orifice and the pressure in chamber 162 is controlled by the angle of inclination of the rewind arm 34 and the instantaneous pressure in line 154 (ie the speed of the machine). Pressure in chamber 162 can never drop below five p.s.i.g. since selecting relay 142 limits pressure in line 154 to five p.s.i.g. and pressure in line 120 is held constant at five p.s.i.g. This pressure of five p.s.i.g. corresponds to the minimum speed that mandrel 30 can be driven. As will be described in connection with FIG. 4, the shape of the theoretical speed curve of the mandrel relative to the diameter of the rewind roll is generally hyperbolic. The contour of the throttling passage can be selected in order to obtain a preselected mandrel speed curve. Valve 168 receives supply air from pipe line 126 at a pressure of twenty p.s.i.g. and also receives air from the chamber 1162. Actually thi valve 168 is merely intended to boost the volume of the mixed air and it does not change the pressure of the air from that contained Within the chamber 162. The air leaves the ratio control station via line 179 which flows past gauge 171 and enters the controller 134.

The controller may be of any suitable commercially available equipment provided it functions in the manner described hereinafter. Moore Products Company of Philadelphia, Pennsylvania produces a controller that is acceptable, which is entilted Nullmatic Controller Model No. 50. The controller 134 receives the controlled air input signal from line 170. Line 132 feeds supply air which is maintained at a constant pressure of thirty p.s.i.g. Speed transmitter 166 discharges, air at a pressure corre- 6 spending to the actual speed of the gear 53; from whence the air passes to the controller 134 via line 156. Line 172 is a feed back line and line 174 is the discharge line from the controller 134. In operation when the air pressure received from the ratio control station122 via line 17%) is greater than that received from line 156, then the controller 134 increasesthe pressure in the discharge line 174. Conversely when the pressure in line 156 is greater than that received from line then the pressure in line 174 will be decreased. The feed back line 172 is provided in order to prevent the controller from overcompensating for such pressure variations and thus helps to prevent hunting.

The air in line 174 after leaving the controller 134 passes through a valve 176 which is merely a manually operated by-pass valve so that the clutch 55 may be either manually controlled, or .it may be controlled by means of the controller 134 mentioned heretofore. The air passes from valve 176 to the amplifying relay 148 via line 177 containing gauge 178. The amplifying relay 148 also receives supply air from line 144 and discharges into line 1%. In effect the amplifying relay merely is a multiplying booster for the air received from line 177. After passing through the amplifying relay 148 and into line 18% the air is divided into two lines 182 and 184. Pressure gauge 186 is provided. The air from lines 182 and 184 is directed against two single acting, spring return pistons positioned within air cylinders 183 and 190, respectively. Thus, the force of the clutch plate 54 (see also FIG. 2) acting against the driven clutch plate 56 operates in response to the pressure introduced into the air cylinders 188 and 190.

In the event that the by-pass valve 176 is positioned for manual operation, the supply air passes through line 144 Where part of itpasses to a manually adjustable regulator 146 While the remainder of the air in line 144'passes directly to the amplifying relay 148 to operate in the same manner as heretofore described. The air passing through the adjustable regulator 146 is controlled manually, as desired, by the operator. After the air leaves the regulator 146 it passes through line 177 and from there into the amplifying relay 148 and operates theclutch plate 54 in the ame manner as heretofore described.

Referring now to FIG. 4, the terms and abbreviations herein employed refer, for illustration only, to the front rewind portion and are as follows:

V=Machine or web speed.

N =The speed (r.p.m.) of the mandrel 30. D=Diameter of rewind roll 26.

N =Shaft speed of motor 38.

P=Pneumatic pressure output of transmitter 104. A=A constant.

K =A constant.

K =A constant.

According to the general'formula:

V V=1rDN V I Nm; But:

NWK1V OI Therefore:

N K N v N m TDKF 1) where:

When N is a constant having an assumed'value of. 1750 rpm. at V=1000 f.p.m. or when N is a'constant having 7 an assumed value of 875 r.p.m. at V=500 f.p.m. then the resulting curve of N vs. D is a hyperbola.

If we substitute the pneumatic pressure output of transmitter 104 for N (since pressure is directly proportional to r.p.m.), then we can plot P vs. D. In this instance fourteen p.s.i.g. represents the maximum rpm. and three p.s.i.g. represents zero r.p.m. Since rpm. and therefore pressure is inversely proportional to diameter, P at any diameter can be written as follows:

3.5 P X A) 3 Where:

Therefore, when D=20 inches Then:

Further, the pressure at D=3.5 inches and at any V will also be proportional to V and can be written as follows:

Since: P=14 p.s.i.g. when D=3.5 inches and V=1000 f.p.m.

Then, when D=3.5 inches and V=500 f.p.m. then:

500 P- (14 3) +3-8.5 p.s.1.g.

Hence, when D=20 inches and V=500 f.p.m. then:

500 P (4.9 3) +3-3.95 p.s.1.g.

The curve of the pressure (P) vs. the diameter (D) at V=l000 f.p.m. and V=500 f.p.m. can be drawn asshown by the broken lines in FIG. 4.

The nature of valve 122 is such that a constant pressure applied to its through line 154 will result in a varying pressure output in line 170 as needle valve 160 is adjusted. A constant back pressure is also required in line 120. By properly selecting the gearing 108 driving knob 110 by a gear 111 fixedly attached to the rewind arm (FIG. 1), output pressure in line 170 (FIG. can be made to vary according to a decreasing relationship as the diameter builds-up. When V=1000 f.p.m., the pressure in line 154 is 14 p.s.i.g. (for maximum web speed) and the pressure in line 120 is five p.s.i.g., then the actual pressure curve is shown by the solid line in FIG. 4. Analogously, the other solid line in FIG. 4 illustrates the actual pressure when V=500 f.p.m.

Thus, the two curves indicating required pressure and actual pressure are superimposed as seen in FIG. 4. It will be appreciated that since the pressure in chamber 162 can never drop below 5 p.s.i.g., then the pressure in line 170 can never drop below 5 p.s.i.g. and, therefore, the actual pressure curve has a minimum limit or cut-off line of 5 p.s.i.g. (shown by the horizontal solid line in FIG. 4) regardless of the required pressure. This pressure of 5 p.s.i.g. corresponds to the minimum speed that mandrel 30 can be driven.

It will be noted that the difference between actual pressures and pressures required represents an overspeed pressure or mandrel overspeed which is required for successful operation. As a practical matterit is usually desirable to operate the rewind shaft with some overspeed over the entire range of operation. Therefore, a gear ratio between gear 58 and the rewind roll shaft 30 is selected which provides an overspeed of the order of approximately to If the output pressure in line 170 is then fed to controller 134 and actual mandrel speed or pressure is fed to the controller via line 156, the two pressures will be compared. If there is a difference between these latter two pressures, the output from line 174 will feed to relay 143 and ultimately cylinders 188 and 190 to either increase or decrease torque output of clutch 55 in order to correct the speed of mandrel 30. If speed of mandrel 39 is correct the pressure in line 156 will be in balance with pressure in line 179. The speed of mandrel 30 will therefore at all times be dictated by the pressure output of valve 122.

In summary three different signals are provided which coact to control the speed of the driven member of the clutch 55. First the speed of the motive means or electric motor 38. Secondly, the angle of inclination of the rewind arms which are responsive to the build-up of the rewind rolls and thirdly, the actual speed of the driven member or" the clutch or the gear 58 which is directly connected thereto. Thus, the rotational speed of the rewind shaft 30 is carefully regulated throughout the entire cycle of operation. Final speed adjustment of each individual rewind roll is obtained by means of the slight slippage which occurs between the rewind roll cores and their respective driving collars.

The control of the angle of inclination on the rewind arms 34 and 36 may be supplied by suitable means known to those skilled in the art such that the nip force between the idler drum 22 and the rewind rolls 26 and 28 may be maintained at preselected values throughout the rewind cycle. In other Words the axes of the respective rewind rolls must be gradually moved away from the contact drum as they build-up or increase in diameter during the rewind process. For example, apparatus suitable for this purpose is disclosed in US. Patent No. 2,872,126 granted February 3, 1959. If desired, the operator may manually adiust said arms to obtain the desired results.

Although particular embodiments of the invention are herein disclosed for purposes of explanation, further modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. Reference should accordingly be had to the appended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. In a rewind machine a combination of a plurality of rewind arms pivotally supported at their inner ends and each pair being adapted to support a rewind shaft at their outer end on which shaft webs of sheet material are to be Wound into rewind rolls, a contact drum in operational engagement with said rewind rolls, means for varying the angle of position of each of said pair of arms in accordance with the diameter of their respective rewind rolls, one of said arms of each pair carrying at its outer end means for driving engagement with said shaft, slip clutch means having the driven sides drivingly connected to said means for driving engagement, motive means having a plurality of power outputs drivingly connected to the driving side of said clutches respectively, control means for controlling the slip of each of said clutch means, each of said control means comprising a speed transmitter for sensing the speed of its respective motive means output and transmitting a corresponding signal, a second speed transmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding signal, a constant signal transmitter, a selecting relay for receiving signals from said first speed transmitter and said constant signal transmitter and transmitting a corresponding signal, means for sensing the angle of position of said rewind arm and transmitting a corresponding signal, a ratio control station for receiving said selecting relay signal and the signal of said means for sensing the angle of position of the rewind arms and for transmitting a corresponding signal, and a controller which actuates its respective clutch means according'to the signals received from said ratio control station and said second speed transmitter.

2. The rewind machine in accordance with claim 1 wherein said means for driving engagement comprises means for individually controlling the speed of each rewind roll.

3. In a rewind machine a combination of a plurality of rewind arms pivotally supported at their inner ends and each pair being adapted to support a rewind shaft at their outer ends on which shaft webs of sheet material are to be wound into rewind rolls, a contact drum disposed in operational engagement with said rewind rolls, means for varying the angle of position of each of said pair of arms in accordance with the diameter of their respective rewind rolls, one of said arms of each pair carrying at its outer end means for driving engagement with said shaft, said means for driving engagement comprising means for individually controlling the speed of each rewind roll, slip clutch means having the driven sides drivingly connected to said means for driving engagement, motive means having a plurality of power outlets drivingly connected to the driving sides of said clutches respectively, control means for controlling the slip of each of said clutch means, each of said control means comprising a speed transmitter for sensing the speed of its respective motive means and transmitting a corresponding pneumatic signal, a second speed transmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding pneumatic signal, a constant pneumatic signal transmitter, a selecting relay for receiving signals from said first speed transmitter and said constant signal transmitter and transmitting a corresponding pneumatic signal, mechanical means for sensing the angle of position of said rewind arms and transmitting mechanical motion corresponding thereto, a ratio control station for receiving said pneumatic signal from said selecting relay signal, said ratio control station having means for receiving said mechanical motion transmitted by said means for sensing the angle of position of the rewind arms and for transmitting a pneumatic signal corresponding to the theoretical slip of said slip clutch means, a controller which pneumatically controls the slip of said clutch means according to a comparison of the pneumatic signals received from said ratio control station and from said second speed transmitter.

4. In a rewind machine a combination of two pairs of rewind arms, each pair pivotally supported at their inner ends and adapted to support a rewind shaft at their outer ends on which shaft webs of sheet material are to be wound into rewind rolls, a like plurality of first slip clutch means having the first sides drivingly connected to said rewind shaft, and the second sides drivingly connected to said rewind rolls respectively, first control means for controlling the slip of each of said first clutch means, a contact drum in operational engagement with the rewind rolls, means for varying the angle of inclination of each pair of said arms, one of said arms of each pair carrying means for driving engagement with its respective shaft, a pair of second slip clutches having the driven sides drivingly connected to said means for driving engagement, respectively, motive means having two power outputs drivingly connected to the driving sides of said second slip clutches respectively, second control means for controlling the contact force between the driving sides and the driven sides respectively of said second slip clutches, each of said second control means comprising a first speed transmitter for sensing the speed of its respective power output and transmitting a corresponding signal, means for sensing the angle of position of said rewind arms and transmitting a corresponding signal, a first control member for receiving both of said signals and for transmitting a signal corresponding to a pre-programmed value as demanded by the angular position of said rewind arms as modified by the speed of the respective power output, a second speed transmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding signal, a second control member for receiving said first at their inner ends and adapted to support a rewind shaft at their outer end on which shaft webs of sheet material are to be wound into rewind rolls, a contact drum in operational engagement with the rewind rolls, means for controlling the angle of inclination ofveach pair of said arms, one of said arms of each pair carrying means for driving engagement with its respective shaft, two slip clutches having the driven sides drivingly connected to said means for driving engagement respectively, motive means having a plurality of power outputs drivingly connected to the driving sides of said clutches respectively, control means for controlling the contact force between said driving side and said driven side of each of said clutches, each of said control means comprising a first speed transmitter for sensing the speed of its respective power output and tranmitting a corresponding signal, means for sensing the angle of position of said rewind arms and transmitting a corresponding signal, a first control member for receiving both of said signals and for transmitting a signal corresponding to a pre-programmed value as demanded by the angular position of said rewind arms as modified by the speed of the respective'power output, a second speed transmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding signal, a second control member for receiving said first control member signal and said second speed transmitter signal and transmitting a corresponding signal, and means for varying said contact force according to said second control member signal.

6. In a rewind machine a combination of a plurality of pairs of rewind arms pivotally supported at their inner ends and each pair being adapted to support a rewind shaft at their outer end on which shaft webs of sheet material are to be wound into rewind rolls, a contact drum in operational engagement with said rewind rolls, means for varying the angle of position of each of said pair of arms in accordance with the diameter of their respective rewind rolls, one of said arms of each pair carrying at its outer end means for driving engagement with said shaft, two slip clutches having the driven sides drivingly connected to said means for driving engagement respectively, motive means having a plurality of power outputs drivingly connected to the driving sides of said clutches respectively, control means for controlling the slip of each of said clutch means, each of said control means comprising a speed transmitter for sensing the speed of its respective power output and transmitting a corresponding signal, a second speedtransmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding signal, means for sensing the angle of position of said rewind arms and transmitting a corresponding signal, a first control member for receiving said signals from said first speed transmitter and the signal of said means for sensing the position of the rewind arms, said first control member being adapted to transmit a signal corresponding to a rare-programmed value as demanded for successive received signals, a second control member for receiving said first control member signal and for receiving signals from said second speed transmitter and comparing said signals so received and accordingly actuating its respective clutch means.

7. In a rewind machine the combination comprising two pairs of rewind arms, each pair being pivotally supported at their inner ends, a rewind shaft supported at the outer ends of each of said pair of rewind arms and upon each of said shafts a plurality of cores are mounted and upon each core a web of sheet material is to be wound into a rewind roll, each of said rewind shafts being provided with a like plurality of first slip clutch means 1 1 having the first sides drivingly connected to said rewind shafts and the second sides drivingly connected to said cores-respectively, first control means for controlling the slip of said first clutch means respectively, a contact drum in operational engagement with said rewind rolls, means for varying the angle of position of each of said pair of arms in accordance with the diameter of the respective rewind rolls, one of said arms of each pair carrying at its outer end means for driving engagement with said shafts respectively, a pair of second slip clutches having the driven sides drivingly connected to said means for driving engagement respectively, motive means having a plurality of power outputs drivingly connected to the driving sides of said second clutches respectively, second control means for controlling the slip of said second clutches respectively, each of said second control means comprising a first speed transmitter for sensing the speed of its respective power output and transmitting a corresponding signal, a second speed transmitter for sensing the speed of its respective rewind shaft and transmitting a corresponding signal, means for sensing the angle of position of said rewind arms and transmitting a corresponding signal, a first control member for receiving said signals from said first speed transmitter and the signal of said means for sensing the position of the rewind arms, said first control member being adapted to transmit a signal corresponding to a pre-programmed value as determined for successive received signals, a second control member for receiving said first control member signal and for receiving signals from said second speed transmitter and comparing said signals so received and accordingly actuating its respective clutch means.

References Cited by the Examiner UNITED STATES PATENTS 2,796,222 6/57 Frankel 242-75.5 2,798,677 7/57 Nicholson 242-7551 X 2,872,126 2/59 Rockstrom et a1. 24265 3,086,726 4/63 Aaron 242--65 MERVIN STEIN, Primary Examiner. 

1. IN A REWIND MACHINE A COMBINATION OF A PLURALITY OF REWIND ARMS PIVOTALLY SUPPORTED AT THEIR INNER ENDS AND EACH PAIR BEING ADAPTED TO SUPPORT A REWIND SHAFT AT THEIR OUTER END ON WHICH SHAFT WEBS OF SHEET MATERIAL ARE TO BE WOUND INTO REWIND ROLLS, A CONTACT DRUM IN OPERATIONAL ENGAGEMENT WITH SAID REWIND ROLLS, MEANS FOR VARYING THE ANGLE OF POSITION OF EACH OF SAID PAIR OF ARMS IN ACCORDANCE WITH THE DIAMETER OF THEIR RESPECTIVE REWIND ROLLS, ONE OF SAID ARMS OF EACH PAIR CARRYING AT ITS OUTER END MEANS FOR DRIVING ENGAGEMENT WITH SAID SHAFT, SLIP CLUTCH MEANS HAVING THE DRIVEN SIDES DRIVINGLY CONNECTED TO SAID MEANS FOR DRIVING ENGAGEMENT, MOTIVE MEANS HAVING A PLURALITY OF POWER OUTPUTS DRIVINGLY CONNECTED TO THE DRIVING SIDE OF SAID CLUTCHES RESPECTIVELY, CONTROL MEANS FOR CONTROLLING THE SLIP OF EACH OF SAID CLUTCH MEANS, EACH OF SAID CONTROL MEANS COMPRISING A SPEED TRANSMITTER FOR SENSING THE SPEED OF ITS RESPECTIVE MOTIVE MEANS OUTPUT AND TRANSMITTING A CORRESPONDING SIGNAL, A SECOND SPEED TRANSMITTER FOR SENSING THE SPEED OF ITS RESPECTIVE REWIND SHAFT AND TRANSMITTING A CORRESPONDING SIGNAL, A CONSTANT SIGNAL TRANSMITTER, A SELECTING RELAY FOR RECEIVING SIGNALS FROM SAID FIRST SPEED TRANSMITTER AND SAID CONSTANT SIGNAL TRANSMITTER AND TRANSMITTING A CORRESPONDING SIGNAL, MEAN FOR SENSING THE ANGLE OF POSITION OF SAID REWIND ARM AND TRANSMITTING A CORRESPONDING SIGNAL, A RATIO CONTROL STATION FOR RECEIVING SAID SELECTING RELAY SIGNAL AND THE SIGNAL OF SAID MEANS FOR SENSING THE ANGLE OF POSITION OF THE REWIND ARMS AND FOR TRANSMITTING A CORRESPONDING SIGNAL, AND A CONTROLLER WHICH ACTUATES ITS RESPECTIVE CLUTCH MEANS ACCORDING TO THE SIGNALS RECEIVED FROM SAID RATIO CONTROL STATION AND SAID SECOND SPEED TRANSMITTER. 